Aiming　at　excessive　users　existing　in　a　pico　base　station　(PBS)　of　heterogeneous　networks,　the　resource　allocation　problem　of　maximizing　the　total　uplink　throughput　is　investigated　in　this　paper.　By　deploying　a　relay　node　with　energy　harvesting,　some　users　of　the　PBS　are　transferred　to　the　adjacent　idle　PBS.　The　resource　allocation　problem　is　formulated　as　an　optimization　problem.　The　objective　is　to　maximize　the　total　uplink　throughput　of　users　in　the　PBS　under　the　constraints　of　the　user＇s　minimum　data　rate,　the　energy　consumption,　and　transmission　power　of　the　relay　node.　The　optimal　solution　is　obtained　by　using　the　augmented　Lagrange　multiplier　method.　Simulation　results　show　that　the　proposed　method　has　higher　throughput　compared　with　the　conventional　method　(i.e.,　some　PBS　users　are　transferred　to　the　macro　base　station).　Moreover,　compared　with　the　equal　power　method,　the　proposed　method　has　an　increase　in　terms　of　throughput　to　a　certain　degree.　©　2019　IEEE.